The present disclosure is directed to a sand relief valve which protects against erosion resulting from sand laden crude oil production. Production from an oil well may often include sand which has a tendency to cut, abrade or erode fittings of the apparatus handling the crude production. One important piece of apparatus is a sampling device which obtains a sample of produced oil. The sampling apparatus collects a certain portion of the produced oil and enables storage of this small portion in a separate sample container. The sample is useful in providing an assay of the produced oil. An assay is essential so that the cost of the oil can be determined based on the assay. Also, the chemical constituents which make up the oil are important. For these reasons, it is highly desirable to collect the sample from a large production stream. For instance, the production stream may be quite sizeable but the sample size permitted by the sample storage apparatus is much smaller. One such sampling apparatus is described in U.S. Pat. No. 4,440,032 assigned to the assignee of the present apparatus.
Sampling devices are thus subject to rapid damage if the oil is under substantial pressure and carries abrasive sand in it. The ability of the apparatus to last is in part determined by the volume of sand which is found in the produced oil. It is also partly dependent on the pressure, and is further dependent on other scale factors which may vary from time to time. Whatever the fact, the present apparatus is a protective valving system to be included in a sampler to thereby reduce damage arising from production of sand cut oil.
Flowing oil is ordinarily a good lubricator. This remains true until the flowing oil carries substantially quantities of sand in it. At that juncture, it can quickly erode the metal components which handle the oil and sand. This is especially true where the flow must pass through a valve seat or perhaps a nipple. It also is true where the flow must turn or is otherwise redirected. The abrasive particles carried in the flowing oil abrade the exposed metal surfaces and damage them. This is cumulative and can very quickly totally destroy an operative device such as a crude oil sampler system.
The present apparatus is a protective valving system incorporated in a crude oil sampler device. It is included in the system to prevent damage from sand laden oil flow. Moreover, this apparatus can be used to choke or restrict the flow velocity and thereby reduce downstream damage resulting from the flowing oil which is otherwise abrasive as a result of the sand particles carried in the oil. In one embodiment of the present apparatus, the crude oil sampler has a long or extended portion which is adapted to be attached to a pipeline or extend into some type of container. It has an internal reciprocating rod. The rod normally encloses an axial flow path. In this embodiment, a valve arrangement is placed in the reciprocating rod. It blocks the flow of the produced oil. This blocked flow impinges on a plug which is forced open in the fashion of a check valve. When open, flow through the valve continues but the flow velocity is reduced. The check valve element is exposed to the sand particles in the flowing oil. The present disclosure sets forth a protective valve which is constructed as a resilient insert within a surrounding valve element which is located so that the flowing sand particles impinge against the resilient insert.
In a second embodiment of the present apparatus, at the outlet of the sampling apparatus, a passage flowing therefrom is interrupted by a check valve apparatus. This check valve construction again imposes a valve element including a resilient insert. This construction enables the resilient insert to confront and block the sand particles and thereby avoid impingement against metal components and their consequential erosion. Both embodiments are spring adjustable to control the measure of opening.